JP2004076479A - Joint structure of steel pipe column and steel beam - Google Patents

Abstract

To provide a joint structure of a steel pipe column and a steel pipe beam provided with a joint hardware at a column / beam joint portion which is relatively lightweight and can reduce the cost.
A structure for bolt-joining steel pipe beams (10, 15) having rectangular cross sections having end plates (11, 16) to a metal fitting (2) having a square cross section provided on a steel pipe column (1), wherein the metal fitting (2) is attached to an inner wall. Is formed thick to provide a plurality of first screw holes 4 in the vertical direction of the corner 3 on one of the opposing surfaces, and the first is formed in the vertical direction of the corner 3 on the other opposing surface. A plurality of second screw holes 5 are provided vertically displaced from the first screw hole 4, and the first screw hole 4 or the second screw hole 2 of the joint hardware 2 is provided on both sides of the steel pipe beams 10, 15 of the end plates 11, 16. A bolt insertion hole was provided corresponding to the screw hole 5 of FIG.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a joint structure between a steel pipe column and a steel pipe beam, and more particularly, to a structure for joining a steel pipe column having a square cross section or a circular cross section to a steel pipe beam having a square cross section.
[0002]
[Prior art]
A steel pipe column having a closed cross section is used in many steel structures because of its non-directional cross-section performance and low buckling performance.
However, because of the closed cross section, the hand does not reach into the inside of the steel pipe column from the outside, so that it is not possible to easily attach the beams or other members with bolts when joining the steel pipe column. For this reason, in a large building, a method of joining beams by welding or joining a bracket to a steel pipe column by welding and bolting the beam to the bracket is generally used.
[0003]
On the other hand, in the case of a small-scale steel frame structure such as a house, a small-scale store, or a parking lot, welding and bracket joining are not preferred from the viewpoint of cost and on-site work, and it is desirable that bolt joining can be easily performed.
For this reason, more joining methods have been proposed than before, but the common configuration is as follows.
[0004]
(1) As shown in FIG. 9, a thick tubular metal piece 30 made of cast steel is welded to the steel pipe column 1 at a connection portion between the steel pipe column 1 and the beam 35 (hereinafter, referred to as a column / beam connection portion). (For example, JP-A-4-339937 and JP-A-4-343933), or a reinforcing plate is applied to the steel pipe column 1 to increase the wall thickness to form a column / beam joint.
(2) The end plate 36 is welded to the beam 35 having the H-shaped cross section.
(3) A bolt insertion hole 37 is formed in the end plate 36 of the beam 35, and a screw hole 31 (or a nut-shaped one is provided) is formed in the cylindrical metal member 30 in advance.
(4) The end plate 36 is joined to the cylindrical metal member 30 provided on the steel pipe column 1 with bolts 40, and the beam 35 is joined to the steel pipe column 1.
[0005]
By the way, many proposals have been made as to the joining method of columns and beams in a small-scale steel frame structure as described above, and most of these proposals and currently implemented structures have H-shaped cross sections. A beam is used, and a slightly grooved beam is used.
When an H-shaped cross-section beam is used, the bolt 40 that joins the H-shaped beam to the cylindrical hardware 30 or the reinforcing plate exerts a stress 46 (shown by oblique lines) generated on the flange of the beam 35 as shown in FIG. In order to effectively transmit the beam to the column / beam joint, it is arranged near the middle position of the column width. Therefore, the thickness of the cylindrical metal member 30 and the reinforcing plate is increased even at the middle portion in the width direction. For this reason, the thickness is almost uniformly increased in the width direction.
[0006]
H-section beams have high cross-sectional efficiency and can be easily bolted together with various structural members required for houses and stores, small beams, floor and roof joists, and secondary members such as horizontal braces. Widely used from such.
On the other hand, a square steel pipe having a closed cross section is not used in such a structure at all because it is difficult to join it with other members as described above. However, it has characteristics such as being less likely to be twisted than an H-shaped cross-section beam. Therefore, especially when a frame structure with a long span is desired but a member for preventing torsion cannot be installed in the middle, or the design is more effective than the sectional efficiency. In cases where emphasis is placed on steel, steel pipe beams may be used.
[0007]
[Problems to be solved by the invention]
When joining a steel pipe beam to a steel pipe column, if an attempt is made to join a steel pipe beam having a rectangular cross section according to the above-described conventional technology, there are various problems in terms of the beam being a steel pipe beam and costs, and a new device is required. Become.
In particular, in terms of cost, the conventional technique requires a thick cylindrical metal part, and therefore, the weight of the column / beam joint is large and an expensive cast steel metal is used. There is a problem that it becomes.
[0008]
The present invention has been made to solve the above-described problems, and it is an object of the present invention to provide a joint structure of a steel pipe column and a steel pipe beam having a relatively lightweight, cost-reducing joint hardware at a column / beam joint. It is intended.
[0009]
[Means for Solving the Problems]
The present invention is a structure for bolt-joining a square-section steel pipe beam having an end plate to a square-section joining metal piece provided on a steel pipe column, wherein the joining piece is formed such that a corner portion of an inner wall is thick. A plurality of first screw holes are provided in the vertical direction of the corner on one of the opposing surfaces, and the first screw holes are vertically displaced in the vertical direction of the corner on the other opposing surface. A plurality of second screw holes, and a bolt insertion hole is provided on both sides of the steel pipe beam of the end plate corresponding to the first screw hole or the second screw hole of the joint hardware. .
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
[Embodiment 1]
FIG. 1 is a perspective view showing a main part of a joint structure between a steel pipe column and a steel pipe beam according to Embodiment 1 of the present invention.
In the drawing, 1 is a square steel pipe column, 2 is a cast steel hardware, and is welded between upper and lower square steel pipe columns 1 (the upper square steel pipe column 1 is omitted in the figure) at the column / beam joint. It is a joined cylindrical metal fitting.
[0011]
As shown in FIG. 2, the outer shape of the metal joint 2 is substantially the same as that of the square steel pipe column 1, and is formed in a rectangular cross section. The inner wall is formed so that the corner 3 is thick and the other parts are thin. I have.
Reference numeral 4 denotes a plurality of first screw holes provided in the vertical direction in the vicinity of both side edges (in the vicinity of the thick corner 3) of one of the opposing surfaces, and 5 denotes both sides before opposing orthogonally to this surface. A plurality of second screw holes provided in the vertical direction near the edge.
[0012]
Reference numeral 10 denotes a steel pipe beam having a rectangular cross section which is joined to one of the opposing surfaces of the joint fitting 2, and an end plate 11 is joined to one end by welding. The width of the end plate 11 is substantially equal to or slightly smaller than the width of the joint surface of the joint fitting 2, and the height is formed slightly higher than the height of the steel pipe beam 10. A bolt insertion hole 12 is provided corresponding to the first screw hole 4 provided on one of the opposed surfaces.
[0013]
Reference numeral 15 denotes a steel pipe beam having a rectangular cross section which is joined to a surface orthogonal to the above of the joint hardware 2. An end plate 16 is joined to one end by welding, and a joint hardware is provided on both sides of the steel pipe beam 15 of the end plate 16. A bolt insertion hole 17 is provided corresponding to the second screw hole 5 provided on the other opposite surface of the second 2. Although the case where the width of the steel pipe beam 15 is smaller than the width of the steel pipe beam 10 is shown, both may be the same width. In addition, although the case where the end plate 16 of the steel pipe beam 15 has the same shape as the end plate 11 of the steel pipe beam 10 is shown, both may have different heights.
[0014]
The first and second screw holes 4 and 5 provided in the joint hardware 2 and the screw insertion holes 12 and 17 provided in the end plates 11 and 16 corresponding to the screw holes 4 and 5 are the screw insertion holes 12. , 17 so that the bolts do not interfere with each other when they are screwed into the screw holes 4 and 5 from the screw holes 4 and 5, as shown in FIG.
[0015]
In the present embodiment as described above, when joining the steel pipe beams 10 and 15 to the square steel pipe column 1 via the joint hardware 2, for example, as shown in FIG. The bolts 40 that are in contact with one surface of the bolt 2 and that are inserted through the bolt insertion holes 12 are screwed into the screw holes 4 provided in the joint hardware 2 and fixed.
Further, the end plate 16 of the steel pipe beam 15 is brought into contact with a surface orthogonal to this, and the bolt 40 inserted into the bolt insertion hole 17 is screwed into the screw hole 5 and fixed as described above. At this time, since the screw holes 4 and 5 on the orthogonal surfaces are provided so as to be shifted in the vertical direction as described above, the bolt 40 does not interfere. In addition, when joining the steel pipe beams 10 and 15 to the other orthogonal surface of the joint fitting 2, it can be performed in the same manner as described above.
[0016]
Next, the operation and effect of the present embodiment will be described in comparison with the related art.
In the case of the H-shaped cross-section beam described in the related art, as shown in FIG. 10, the vicinity of the upper center portion of the web of the H-shaped cross-section beam 35 is a region where the stress of the beam 35 due to the bending moment is dominant (FIG. (Indicated by a hatched line 46), it is effective to dispose a bolt (indicated by a bolt insertion hole 37) in the vicinity thereof to transmit the stress.
On the other hand, in the steel pipe beams 10 and 15 having a rectangular cross section as in the present embodiment (hereinafter, the steel pipe beam 10 will be described), as shown by oblique lines 45 in FIG. It is effective to dispose bolts in the vicinity of the stress dominant region, so that the bolt insertion holes 12 of the end plate 11 are provided on both sides of the steel pipe beam 10 along the long side thereof. Was.
[0017]
Generally, the column width is wider than the beam width, and the beam stress caused by the bending moment is measured from the entire surface of the column / beam joint (the surface where the end plate abuts) via the bolt. It flows on a plane perpendicular to this plane (called the panel zone) and is transmitted to the lower pillar.
For this reason, when the conventional H-shaped beam 35 is used, as shown by an arrow in FIG. 11, the stress is transmitted from the bolt 40 to the steel pipe column 1 by largely bending the inside of the cylindrical metal piece 30. In order to make the flow smoothly, the thickness of the cylindrical metal piece 30 must be uniformly thickened, and the cylindrical metal piece 30, which is an expensive cast steel metal piece, becomes more expensive and the weight increases. .
[0018]
On the other hand, in the present embodiment, the end plate 11 is provided with the bolt insertion holes 12 on both sides thereof along the long side of the steel pipe beam 10, so that the bending moment caused by the bending moment as shown by the arrow in FIG. This stress is smoothly transmitted from the bolt 40 to the square steel tube column 1 via the corner 3 of the metal joint 2 without suddenly changing the direction, so that the thickness of the portion other than the corner 3 can be sufficiently reduced.
[0019]
In this case, in general, in a member having a square cross section, the corner of the inner wall is not formed at a right angle, but is formed by an appropriate radius. It may be formed slightly larger, and the thickness of other portions can be greatly reduced.
As described above, in the present embodiment, since the cross-sectional shape of the metal joint 2 is formed as described above, the cost can be reduced when the column / beam joint is formed by the expensive metal joint 2 made of cast steel. In addition, the weight can be reduced and the workability can be improved.
[0020]
In the present embodiment, the bolt connection of the end plate 11 of the steel pipe beam 10 to the vicinity of the corner 3 of the metal joint 2 has a large effect on stress transmission and cost as described above. The problem is that the bolts 40 of the steel pipe beams 10 and 15 joined perpendicularly to each other interfere with each other. This problem was solved by shifting the position of the bolt 40 for fixing the orthogonal steel pipe beams 10 and 15 in the vertical direction as described above.
[0021]
For this reason, it is possible to obtain the effect that the metal fitting 2 provided at the column / beam joint does not need to have a special cross-sectional shape, while the position of the bolt 40 for fixing the steel pipe beams 10 and 15 to be orthogonally joined is determined in the vertical direction. It is necessary to consider structural performance problems caused by the deviation. That is, if the positions of the bolts 40 of the steel pipe beams 10 and 15 that are orthogonally joined to each other are different, it is inevitable that the joining strength of both will change.
[0022]
Generally, a steel frame structure has directionality in required performance. For example, assuming a typical arrangement of columns and beams in a small building as shown in FIG. 7, columns A and B have different spans and different external forces acting in the respective directions. 1 is made of an isotropic square steel pipe or a circular steel pipe, but the required cross-sectional performance is generally different between the beam 10 in the A direction and the beam 15 in the B direction. Therefore, even when the same member is used for the beam (there is often a case of using the same size beam from a viewpoint other than the structure), the joining performance required for orthogonal beams always has a magnitude.
[0023]
In the example of the bolt arrangement shown in FIG. 3, as compared with the case of the bolt arrangement of the steel pipe beam 10, if the bolts of the same size are used in the bolt arrangement of the steel pipe beam 15, the joint strength of the steel pipe beam 15 is higher. Will be weak. However, since the required strength of the steel pipe beam has a magnitude depending on the direction, the steel pipe beam 10 and the steel pipe beam 15 can be joined in accordance with the direction, so that the joint strength does not change in this way. It can be said that it is preferable in terms of balance.
Of course, if the beam size (including the case where the plate thickness is small) is small, there is no problem at all, and if necessary, it can be made equivalent by changing the bolt size. There is no problem in shifting the positions of the bolts of the beams 10 and 15 in the vertical direction.
[0024]
[Embodiment 2]
FIG. 8 is an explanatory view showing a main part of a joint structure between a steel pipe column and a steel pipe beam according to Embodiment 2 of the present invention.
In the first embodiment, a case in which a steel pipe having a square cross section is used for a column is shown. In the present embodiment, a steel pipe having a circular cross section (hereinafter, referred to as a steel pipe column having a circular cross section) is used for a column. Has a structure substantially the same as that of the first embodiment, and a steel pipe column 1a having a circular cross section is welded on the upper and lower sides thereof to form a column / beam joint.
[0025]
Conventionally, when an H-shaped beam is joined to a steel pipe column having a circular section via an end plate, for example, as shown in Japanese Patent Application Laid-Open No. 4-339937, the thickness of the joining cylinder at the bolt screw-in position is reduced. It was necessary to greatly increase the thickness, so that the overall thickness could not be reduced, which not only increased the cost but also increased the weight.
[0026]
In the present embodiment, as shown in FIG. 8, a corner portion 3 is formed to be thick using R in a joining member 2 constituting a column / beam joint portion, and the other portions are thin and hollow inside. A part having a structure almost the same as that of the first embodiment, which is almost circular, can be used.
Therefore, the same operation and effect as those of the first embodiment can be obtained.
[0027]
【The invention's effect】
The joint structure of the steel pipe column and the steel pipe beam according to the present invention, a metal joint having a square cross section to be joined to the column / beam joint portion of the steel pipe column, the other part of the inner wall is formed to be thick at the corner of the inner wall, A screw hole for bolting the end plate of the steel pipe beam is provided at this corner, and a bolt insertion hole is provided on both sides of the steel pipe beam of the end plate corresponding to the screw hole of the joint hardware, so that the end plate is made of cast steel. The weight of the metal joint can be reduced, the cost can be reduced, and the stress caused by the bending moment can be smoothly transmitted to the steel pipe column.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a main part of a joint structure between a steel pipe column and a steel pipe beam according to Embodiment 1 of the present invention.
FIG. 2 is a plan sectional view of the metal joint of FIG. 1;
FIG. 3 is a front view of an end plate of the steel pipe beam of FIG. 1;
FIG. 4 is an explanatory view showing a joining state of a steel pipe beam to the joining hardware of FIG. 1;
FIG. 5 is an explanatory diagram showing a state of stress generated in the steel pipe beam of the first embodiment.
FIG. 6 is an explanatory diagram showing a state of transmitting stress according to the first embodiment.
FIG. 7 is an explanatory diagram showing an example of arrangement of columns and beams in a small building.
FIG. 8 is an explanatory view showing a main part of a joint structure between a steel pipe column and a steel pipe beam according to Embodiment 2 of the present invention.
FIG. 9 is an explanatory view showing an example of a conventional joint structure between a steel pipe column and an H-shaped section beam.
FIG. 10 is an explanatory diagram showing a state of stress generated in the H-shaped section beam of FIG. 9;
FIG. 11 is an explanatory diagram showing a state of transmission of stress in FIG. 9;
[Explanation of symbols]
1, 1a Steel pipe column 2 Joint hardware 3 Corner 4 First screw hole 5 Second screw hole 10, 15 Steel pipe beam 11, 16 End plate 12, 17 Bolt insertion hole

Claims (1)

A structure for bolt-joining a steel tube beam having a square cross section having an end plate to a metal joint having a square cross section provided on a steel pipe column,
The joint metal part is formed such that a corner portion of an inner wall is formed to be thick, and a plurality of first screw holes are provided in a vertical direction of the corner portion on one facing surface, and the corner portion on the other facing surface is provided. A plurality of second screw holes are provided vertically displaced from the first screw hole, and a first screw hole or a second screw of the joint hardware is provided on both sides of the steel pipe beam of the end plate. A joint structure between a steel pipe column and a steel pipe beam, wherein a bolt insertion hole is provided corresponding to the hole.

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